Apparatus for molding



July 27, 1937. M. E. ToMAN APPARATUS FOR MOLDING Filed May 27, 1935 3Sheets-Sheet l IJuly 27, 1937.

M. E. TOMAN APPARATUS FOR MoLDxNG Filed May 27, 1935 VI5 Sheets-Sheet 2Mir/Zee( Y Rizza,

July 27, 1937. M. E. roMAN 2,088,123

APPARATUS FOR MOLDING.

Filed May 27, 1935 3 Sheets-Sheet 3 Hummm@ PatentedcJuly 27, 1937yUNITED STATES 2,088,123 APPARATUS Fon MoLnmG Michael E. Toman, Berwyn,Ill., assignor to Castings Patent Corporation, a corporation of IllinosApplication May 27, 1935, Serial No. l23,677

Claims..

ing material such as asbestos fiber or rubber is placed against the topor bottom side of the mold or sheets or pads of such material may beplaced on both the upper and bottom sides of the mold. The` mold withits sheets or pads is then inserted and clamped between two plates underpressure. The yielding material, which is preferably resilient, permitsor causes the two parts -of the mold to yield or flex, if necessary, tobring the parting surfaces of the mold members into full and completecontact with each other. This insures that the casting obtained from themold will not have any appreciable fin at the parting line.

Other objects and advantages will become apparent as the followingdetailed description progresses, reference being had to the accompanyingdrawings, wherein- Fig. 1 is a front elevation of apparatus for holdinga mold, under pressure, during. the molding operation.

Fig. 2 is a section taken on line 2--2 of Fig. 1.v

Fig. 3 is a section taken on line 3-3 of Fig. 1. Fig. 4 is an enlargedfragmentary section taken on line 4-4 of Fig. 1.

Fig. 5 is a section taken on line 5-5 of Fig. 4. Fig. 6 is an enlargedfragmentary section taken on line 6 6 of Fig. 1.

Fig. 7 is a longitudinal section taken through a sheet or a pad ofyielding material, which sheet or pad embodies a modified form of theinvention. Fig. 8 is a longitudinal section taken through a sheet or padof yielding material, which sheet y or pad embodies another form of theinvention.

Fig. 9 is a fragmentary central section taken through apparatusembodying another form of the invention.

Fig. 10 is a perspective view of a hollow sheet metal pad which embodiesstill another form of the invention, and

Fig. 11 is a section taken on line H-ii of Fig. 10.

rlihe apparatus shown in the accompanying drawings is particularlyadapted to be employed Rtlssutn MAYJ 2 1 1940 (ci. zz-so) M inconnectionwith molds formed from calcined gypsum, asbestos pulp andwater. The pattern is usually formed in metalupon a metallic matchplate, the as'k being secured to the match plate and being provided witha cover plate. The ma- 5 terials from which the mold is to be formed arepreferably placed therein and violently agitated after which the mold ispermitted to set. The mold is then removed from the flask and issubjected to a drying operation. The dried mold is 10 extremely porousand when fused metal is poured into it, the lgases evolved during` thepouring operation vent through the body of the mold. Of course, it isreadily understood that the mold is made in two or more parts separatelyformed 15 in suitable flasks which may be identical with each other inconstruction.

It may be mentioned at this point in the description that during thedrying operation, the molds have some tendency to warp and, in some 20instances, different parts of the mold shrink different amounts. It hasbeen found that when the parting faces of the two halves of a mold arenot exactly complementary to eachother, the metallic casting obtainedfrom the mold will 25 oftentimes have a iin which must be removed. This,of course, increases the cost of producing castings in' quantity as eachindividual casting must be handled during the operation of removing thefins. 30

As indicated above, the mold members are removed from the flasks beforethey are assembled for the pouri'ng operation. In fact, it has beenfound preferable to remove them from the flasks before the dryingoperation. When a mold is to 35 be poured, the bottom member of it maybe placed upon any suitable support and the top member is then placedupon the lower member and subjected to pressure so that the two parts ofthe mold will not separate during the pouring opera- 40 tion.

Referring now to Figs. 1 to 6, inclusive, wherein improved apparatusembodying the invention is disclosed, the reference character lildesignates generally a frame which comprises legs i i adapt 45 ed tosupport the apparatus upon any suitable support such as a foundry floor.The upper ends of the legs are tied to each other by cross members i2and i3 and extending upwardly from the cross members i3 are uprights l5which are bolt- 50 ed at their upper ends to a cross member it. The,frame is strengthened by relatively large plates iwhich are bolted tosome of the crossmembers i3 and to the uprights i5.

The cross members i2 carrying a plate 2t 55 adapted to support the moldsduring the pouring operation. In Figs. 1 to 6, inclusive, a mold isidentified generally by the reference character 22 and comprises abottom half or member 23 and a top member or half 24, the mold beingformed with the usual mold cavity 25 and a pouring passage or sprue 26.In this instance, part of the mold cavity 25 is formed in the moldmember 24 and part in the mold member 23. However, in some instances,the mold cavity is formed entirely in one of the mold members a1- thoughthe mold cavity is closed by the other mold member.

A pad 30 is disposed between the plate 20 and the bottom surface of themold 22, a similar pad 3| being vinserted between the top surface of themold 22 and a relatively heavy plate 33 which is provided with anaperture 36 adapted to receive a sprue member 31 having a passage whichcommunicates with the sprue 26. It will be noted that the plate 33 isprovided with an annular shoulder 38 which engages a similar shoulder onthe sprue 31 and holds the sprue 31 in contact with the top surface ofthe mold member 24.

Abutting against the top surface of a boss 40 formed integral withAtheplate 33 is a plunger 42 which projects from the bottom end of avertically disposed cylinder 43 depending from and secured to the crossmember I6. 'I'he upper end of the plunger 42 is secured to a piston 45slidably journaled in the piston and urged upwardly by a. compressionspring 46. The upper end of the piston 43 communicates through a tube 49With a port 50 in a valve casing 5| provided with additional ports 52and 53, the port 53 being an exhaust port. A valve plug (Figs. 1 and 6)rotatably journaled in the valve casing 5| and adapted to be displacedangularly by a lever 51 is provided with a passage 58 extendingdiametrically thereof and adapted to connect the ports 50 and 52 to eachother. The valve plug 55 has another passage 59 communicating with thepassage 58. The port 52 is` connected to any suitable supply (not shown)of uid under pressure by a pipe 60. When the valve plug is in theposition wherein it is shown in Fig. 6, the,

fluid, under pressure, will flow from the pipe 88, the port 52, thepassage 58, the port 50 and thence through the tube 49 to the cylinder43 to force the piston 45 and the plunger 42 downwardly against 'theaction of the spring 45. Ex-

` cellent results have been obtained when the apparatus is adjusted sothat the mold is subjected to a pressure ranging from 1.5 pounds persquare inch to a pressure of 2.5 pounds per square inch. Of course, themold is subjected to this pressure during the pouring operation andduring the initial cooling operation.

After a mold has been poured, the valve plug 55 is displaced in acounter-clockwise direction (Fig. 6) so that the outer end of thepassage 53 communicates with the port 50 and one end 'of the passage 58communicates with the exhaust port 53. The valve plug 55 then shuts oi!the supply (not shown) of uid under pressure and permits the piston 43to exhaust through the tube 48, the port 50, the passages 59 and 58, andthence through the exhaust port 53. This permits the spring 46 toelongate and lift the plunger 42 from the plate 33 so that it may beremoved.

The pads 30 and 3| may be formed of various yielding substances oryielding members. In that form of the invention illustrated in Figs. 1to 6, inclusive, the pads 38 and 3| are formed aoaaiae of relativelythick sheets 'i6 -of sponge rubber, each sheet 'l0 being faced on oneside by a sheet of asbestos 12, the asbestos sheets 12 abutting againstthe adjacent surfaces of the mold 22 and protecting the rubber sheets 10from the heat of the fused metal introduced into the mold cavity.

In practice it has been found that the yielding pads 30 and 3| willfunction in such manner that if the mold members set and dry so that theparting line between the mold members 23 and 24 do not contact eachother throughout when one is placed upon the other, the pads 30 willyield where the mold members contact each other and will aid in flexingthe mold members into shapes wherein the entire parting surfaces thereofcontact wlth each other. Oi course, when the yielding members are formedof sponge or relatively soft rubber, they yield a relatively largeamount when they are subjected to the pressure set forth above..

'I'he operation of the apparatus illustrated in Figs. 1 to 6, inclusive,is substantially as follows: After the mold 22 has been formed in themanner described above, the two parts 23 and 24 thereof are assembledwith the pads 38 and 3| and inserted between the plates 20 and 33, theplate 33 being lifted from a suitable bench, or the equivalent, andplaced upon the pad 3| with the sprue member 31 in place. The valve plug55 is then adjusted so that the fluid, under pressure, exerts its forceupon the plate 33 and clamps the mold members 23 and 24 and the pads 30and 3| between it and the plate 20. The fused metal is then poured intothe mold in the usual manner and after it has set and cooled asufficient length of time, the valve plug 55 is displaced angularly sothat the fluid, under pressure, will be exhausted from the cylinder 43,whereupon the spring 46 will elongate and move the plunger 424 upwardly.The plate 33 may then be removed from the mold and the mold may beplaced upon any convenient support until it is to be broken to removethe casting therefrom.

It has been found that when molds are produced by practicing the methoddescribed above, they are substantially free from fins at the parti ingline or lines.

In Fig. 7, a pad 30a formed of asbestos ilber is shown. This pad may beemployed inplace of either of the pads 30 or 3| described above. The pad38a is formed'from braided asbestos ber.

In Fig. 8, a pad 30h is shown which may be employed in place of the pads30 and 3l.` 'I'he pad 38h is formed from rubber. It is readilyunderstood that the pads 38a and 38h maybe superimposed upon each otherand employed in place of the pads 30 and 3| described above.

In Fig. 9, a mold' 22e identical with the mold 22 is shown. -The mold22c comprises mold members 23c and 24c formed of calcined gypsum,asbestos pulp and water. In this instance as in the instance describedabove, substantially all the free water and a relatively large part ofthe water in chemical combination has been removed from the mold members23o and 24c during the drying operation so that they are extremelyporous. The bottom mold 23c rests upon a relatively thin sheet metalplate 8l which forms a closure for a chamber 3| connected to anysuitable source (not shown) of fluid under pressure through a valve 32.In some instances, the` chamber Il will be nlled with compressed nir toa suitable pressure and in other instances. the chamber 3| will befilled with water. However, it is contemplated that in both instanc thesheet metal member Il will flex and function in the same manner and forthe same purpose as the pads 30 and 3i described above. The upper moldmember 24e has a weight 85 resting upon it, which weight is apertured tohold the sprue member 86 having the same function as the sprue member 31described above.

In Figs. and 11, another embodiment of the invention is illustrated.Thus, a hollow metallic pad is designated generally by the referencecharacter 90 and comprises top and bottom walls 9i and 92, respectively,which have their marginal portions welded to each other. The walls 9|and 92 are formed froinrelativelyy thin sheet metal and form a chamber93 into which compressed air or water may be introduced through a pipe95. It is contemplated that the pad 90 may be employed in place of thepads 30 and 3| and that it will yield and function in substantially thesame manner as the pads 30 and 3l.`

While I have shown and described certain embodiments of my invention. itis to be understood that it is capablel of many modifications. Changes,therefore, in the construction and arrangement may be made withoutdeparting from the spirit and scope of the invention as disclosed in theappended claims, in which it is my intention to claim all noveltyinherent in my invention as broadly as permissible, in View of the priorart.

1. Apparatus for clamping complementary mold members against each otherfor the pouring operation, which apparatus comprises a rubber pad, andmeans acting through said rubber pad for forcing the mold membersagainst each other to have the parting surfaces thereof held firmly incontact with each other around the mold cavity, said rubber pad yieldingunequally as necessary in different parts thereof to compensate forfaults in the mold members.

2. Apparatus for clamping complementary mold members against each otherfor the pouring operation, which apparatus comprises an asbestos pad,and means acting through said asbestos pad for forcing the mold membersagainst each other to have the parting surfaces thereof held firmly incontact with each other around the mold cavity, said asbestos padyielding unequaily as neces-y sary in different parts thereof tocompensate for faults in the mold members.

3. Apparatus for clamping complementary mold members against each otherfor the pouring operation, which apparatus comprises a pad of resilientmaterial, and means acting through said pad for forcing the mold membersagainst each other to have the parting surfaces thereof held firmly incontact with each other around the mold cavity, said pad yieldingunequaily ask necessary in different parts thereof to compensate forfaults in the mold members.

4. Apparatus for clamping complementary mold membersagainst each otherfor the pouring operation, which apparatus comprises a padlike memberwhich "is compressible in substantially all parts thereof, and meansacting through said pad-like member for forcing the mold members againsteach other to have the parting surfaces thereof held firmly in contactwith each other around the mold cavity, said pad-like member yieldingunequaily as necessary in different parts thereof to compensate forfaults in the mold members.

5. Apparatus for clamping complementary mold members against each otherfor the pouring operation, which apparatus comprises resilient meansacting on a surface of one of said ent parts thereof to compensate forfaults in the y mold members. 6. Apparatus for clamping complementarymold members against each other for the pouring operation, whichapparatus comprises resilient means having a large area acting on asurface of one of said members, said area being at least as large as thearea of the mold cavity at the parting line between the mold members,and means acting through said resilient means for forcing the moldmembers against each other to contact parting surfaces thereof heldfirmly in contact with each other around the mold cavity, said yieldingmeans yielding unequaily as necessary in different parts thereof tocompensate for faultsin the mold members.

7. Apparatus for clamping complementary mold members against each otherfor the pouring operation, which apparatus comprises a hollow member,and means acting through said hollow member for forcing the mold membersagainst each other to have the parting surfaces thereof held firmly incontact witheach other around the mold cavity, said hollow memberyielding unequally as necessary in different parts thereof to compensatefor faults in the mold members.

8. Apparatus for clamping complementary mold members against each otherfor the .pouring operation, which apparatus comprises a. memberincluding a flexible sheet of metal, and means acting through saidflexible sheet of metal for forcing the mold members against each otherto have the parting surfaces thereof held firmly in contact with eachother around the mold cavity, said flexible sheet of metal yieldingunequaily as necessary in different parts thereof to compensate forfaults in the mold members.

9. Apparatus' for clamping complementary Vmold members against eachother for the pouring operation, which apparatus comprises a layer ofyielding material, and means acting through said yielding material forforcing the mold members against each other to have the parting surfacesthereof held rmly in contact with each other around the mold cavity,said yielding material yielding unequaily as necessary at differentpoints to compensate for faults in the mold members.

10. An apparatus for clamping complementary mold members against eachother for the pouring operation, said apparatus comprising spacedclamping members receiving the complementary mold members therebetween,one of said clamping members having a sprue opening therein, saidapparatus comprising a pad of resilient material interposed between oneof said clamping members and the mold members, said pad being normallyof even thickness over its active area, but being yieldable unequaily asnecessary in different parts thereof to compensate for faults in themold members.

MICHAEL E. TOMAN.

